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Founded in 1932, Journal of Animal Ecology publishes original
research papers on all aspects of animal ecology; specifically those that make
substantial contributions to our understanding of animal ecology as well as
offering insights into issues of general interest to ecologists. This includes
reviews that shed light on subjects central to animal ecology, including theoretical
analyses of specific topics. The Journal publishes standard papers, essay reviews,
forum pieces and In Focus articles (by invitation). The journal is published
six times a year. Further details are available at www.journalofanimalecology.org.
JSTOR provides a digital archive of the print version of The Journal
of Animal Ecology. The electronic version of The Journal of Animal
Ecology is available at http://www3.interscience.wiley.com/journal/117960113/home.
Authorised users may be able to access the full text articles at this site.

The "moving wall" represents the time period between the last issue
available in JSTOR and the most recently published issue of a journal.
Moving walls are generally represented in years. In rare instances, a
publisher has elected to have a "zero" moving wall, so their current
issues are available in JSTOR shortly after publication.
Note: In calculating the moving wall, the current year is not counted.
For example, if the current year is 2008 and a journal has a 5 year
moving wall, articles from the year 2002 are available.

Terms Related to the Moving Wall

Fixed walls: Journals with no new volumes being added to the archive.

Absorbed: Journals that are combined with another title.

Complete: Journals that are no longer published or that have been
combined with another title.

Abstract

1. Understanding the interactions between different periods of the annual cycle in migratory animals has been constrained by our inability to track individuals across seasos. In seabirds, virtually nothing is known about how diet quality during the non-breeding period, away from the breeding grounds, might influence subsequent reproductive success. 2. We used stable nitrogen (δ13N) and carbon (δ13C) isotopes to evaluate the effects of non-breeding diet quality on the timing of breeding and egg size in a population of Cassin's auklets (Ptychoramphus aleuticus) breeding on Triangle Island, British Columbia. Adult feathers are grown during two different periods of the annual cycle, which allowed us to estimate diet quality from the previous fall (October—November) and pre-breeding (February—March) period. 3. We found that the estimated proportion of energetically superior copepods (Neocalanus spp.) in the pre-breeding diet tended to be higher in females that bred earlier and laid larger eggs, whereas energetically poor juvenile rockfish (Sebastes spp.) were dominant in the pre-breeding diets of females that bred later and laid smaller eggs. We detected no effect of fall diet quality on breeding date or egg size, and no effect of pre-breeding diet quality on breeding date in males. 4. Pre-breeding diet quality was not related to body condition measured 1—2 days after laying, which suggests that females may need to attain a threshold condition before they initiate breeding and successfully rear young. 5. Our results suggest that changes in climatic conditions during the pre-breeding period may have severe consequences for reproductive success by influencing breeding date and egg size. Our work emphasizes the importance of determining how events are linked throughout the annual cycle for understanding the fitness and population dynamics of migratory animals.